Marek Blahušiak - Academia.edu (original) (raw)
Papers by Marek Blahušiak
Separation and Purification Technology, 2018
Separations account for approximately 50% of all manufacturing costs, making the selection of the... more Separations account for approximately 50% of all manufacturing costs, making the selection of the proper technology, and a potential affinity separation agent (ASA) of essential importance for process design. This selection is not straightforward. In this paper, aspects of fluid separation technologies, including shortcut calculations to estimate heat duties, are reviewed and applied to create insights in ab initio fluid separation process selection without extensive process simulations. It was found that composition and state of the feed can have major impacts on the minimal required heat duty, as well as the desired product purity. Distillation of dilute feeds is intrinsically hindered by a low internal efficiency and solvent based separations should be considered. Furthermore, the minimal heat duty for liquid-liquid extraction (LLX) with high boiling solvents is primarily feed composition dependent, while for low boiling solvents the solvent to feed ratio is important. This is also the case for the minimal duty for extractive distillation (ED) with light solvents, whereas the minimal duty of ED using high boiling solvents is independent of the composition, and generally higher than the minimal LLX duty. ED can be operated with only two columns, whereas LLX generally requires at least three, leading to higher capital costs. The feed composition dependence of the LLX minimal heat duty can result in a feed compositional break-even point when comparing LLX with ED. Using these theoretical insights in fluid separations, a series of industrial cases was reviewed and critical aspects in technology selection, and solvent selection and design such as selectivity and capacity are discussed. The results confirm the applicability of the minimal heat duty approach as a quick prediction tool for opportunities of solvent based technologies, as well as the need for including other considerations such as the number of required columns (capital costs) and the possibility to recover sensible heat.
International Journal of Environmental Research and Public Health, Nov 22, 2021
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Energy Efficiency, Jun 25, 2019
Intending to contribute to the discourse about industrial energy efficiency and barriers to its i... more Intending to contribute to the discourse about industrial energy efficiency and barriers to its improvement, deep insight into the scope and methodology and achievements of an energy audit on a Catalytic Naphtha Reforming Unit are provided. The audit of this particular unit was a part of the audit of the whole SLOVNAFT refinery in 2010-2012. The audit itself is the preparation of saving proposals' implementation and postimplementation monitoring and targeting that lasted until spring 2016 covered in retrospective as the auditors were involved in all post-auditing phases as well. Several saving ideas emerging from the performed audit were rejected or have still not been implemented due to either technical issues or non-technical factors. Implemented proposals included improvement in the condensates' management system, boiler feedwater preparation, and increased exploitation of the cogeneration potential. A cumulative 3-year benefit of over 600 k€ is reported which is close to the targeted value. The postaudit cooperation of auditors with the refinery's staff enabled to define the non-technical barriers to saving proposals' adoption that are of general nature. These included (1) short payback period requirement, (2) possibility of implementation of changes during the turnaround/general revisions, (3) conflicting relationships between local micro-economies of production units and the net-economy of the whole refinery, (4) internal processes and communication, and (5) personnel policy. Long-term cooperation, winning the trust and support of the staff and managers, and regular monitoring and targeting of implemented measures are seen as essential parts of sustainable industrial energy efficiency improvement in any industrial energy auditing.
![Research paper thumbnail of Corrigendum to “Physical properties of phosponium ionic liquid and its mixtures with dodecane and water” [J. Chem. Thermodyn. 72 (2014) 54–64]](https://attachments.academia-assets.com/116496769/thumbnails/1.jpg)
](The Journal of Chemical Thermodynamics, Feb 1, 2016
International Journal of Environmental Research and Public Health, 2021
Steam crackers (ethylene plants) belong to the most complex industrial plants and offer significa... more Steam crackers (ethylene plants) belong to the most complex industrial plants and offer significant potential for energy-saving translated into the reduction of greenhouse gas emissions. Steam export to or import from adjacent units or complexes can boost the associated financial benefit, but its energy and environmental impact are questionable. A study was carried out on a medium-capacity ethylene plant using field data to: 1. Estimate the energy savings potential achievable by optimizing internal steam management and optimizing steam export/import; 2. Quantify the associated change in air pollutant emissions; 3. Analyze the impact of the increasing carbon price on the measures adopted. Internal steam management optimization yielded steam let-down rate minimization and resulted in a 5% (87 TJ/year) reduction in steam cracker’s steam boiler fuel consumption and the associated cut of CO2 emissions by almost 4900 t/year and that of NOx emissions by more than 5 t/year. Steam import to ...
Large industrial production plants utilize steam as process and heating medium typically at least... more Large industrial production plants utilize steam as process and heating medium typically at least at two pressure levels. Such industrial facilities are also typically equipped with high pressure steam boilers and backpressure or/and condensing steam turbines, to cogenerate both process/heating steam and electricity for own consumption at the same time. Steam produced in steam turbines and exported from the cogeneration unit often undergoes pressure control step prior being consumed in the process or condensed in a heat exchanger. Contributing to production process stability on the one hand, such pressure reduction may result in decrease of cogenerated electric energy amount. In our study, we focused on paper machines as large steam consumers in papermaking process and the impact of low and medium pressure steam utilization in a thermocompressor installed in a particular paper machine on the RES-based cogeneration unit electric energy output. Thermocompressor is often applied in ind...
Energy Efficiency, 2019
Intending to contribute to the discourse about industrial energy efficiency and barriers to its i... more Intending to contribute to the discourse about industrial energy efficiency and barriers to its improvement, deep insight into the scope and methodology and achievements of an energy audit on a Catalytic Naphtha Reforming Unit are provided. The audit of this particular unit was a part of the audit of the whole SLOVNAFT refinery in 2010-2012. The audit itself is the preparation of saving proposals' implementation and postimplementation monitoring and targeting that lasted until spring 2016 covered in retrospective as the auditors were involved in all post-auditing phases as well. Several saving ideas emerging from the performed audit were rejected or have still not been implemented due to either technical issues or non-technical factors. Implemented proposals included improvement in the condensates' management system, boiler feedwater preparation, and increased exploitation of the cogeneration potential. A cumulative 3-year benefit of over 600 k€ is reported which is close to the targeted value. The postaudit cooperation of auditors with the refinery's staff enabled to define the non-technical barriers to saving proposals' adoption that are of general nature. These included (1) short payback period requirement, (2) possibility of implementation of changes during the turnaround/general revisions, (3) conflicting relationships between local micro-economies of production units and the net-economy of the whole refinery, (4) internal processes and communication, and (5) personnel policy. Long-term cooperation, winning the trust and support of the staff and managers, and regular monitoring and targeting of implemented measures are seen as essential parts of sustainable industrial energy efficiency improvement in any industrial energy auditing.
Energy Efficiency, 2019
BFWH Boiler feedwater heater BL Black liquor CCT Condensates collection tank CONC Concentrator CO... more BFWH Boiler feedwater heater BL Black liquor CCT Condensates collection tank CONC Concentrator COND Condenser DEA Deaerator ECO Economizer ESP Electrostatic precipitator FG Flue gas FGC Flue gas cooler HDS High dry solids HERB High energy regeneration boiler HPS High pressure steam (around 20 bar(g)) HW Hot water LPS Low pressure steam (around 5 bar (g)) MPS Middle pressure steam (around 11 bar (g)) OH Operating hours (per year) P&P Pulp & paper RS Reference state ST Steam turbine TIC Total investment cost VHPS Very high pressure steam (above 40 bar (g)) W Intercept of steam turbine working characteristics in Eqs.
Chemical Papers, 2017
An overview on specific phenomena in extraction of carboxylic acids with hydrophobic ionic liquid... more An overview on specific phenomena in extraction of carboxylic acids with hydrophobic ionic liquids (ILs) based on results of new measurements with selected phosphonium, ammonium and imidazolium ILs and published data is presented. Formation of IL-acid hydrated complexes with multiple molecules of organic acid per one IL ion pair was observed. The distribution coefficient of carboxylic acids and water content in ILs strongly decreases with the increasing acid concentration. Dependence of water content in the solvent passes through a minimum at loading of IL with butyric acid of about 3. Two extraction mechanisms are involved: competitive extraction of acid and water with the release of water from the solvent and co-extraction of water with acid depending on the IL concentration. A strong synergistic effect was observed between the cation and anion of ILs enhancing their extractive properties compared to IL precursors. A new extraction model suggests the formation of water bridges and polar nano-channels which is in agreement with the molecular modelling results. ILs are nano-segregated liquids with a structure sensitive to the content of molecular compounds. Water and carboxylic acids accumulate in polar domains and dodecane in non-polar domains modifying the IL structure and decreasing the solvent phase viscosity. The hypothesis of hopping mechanism in polar channels for acid molecules transport between acid chains at IL binding sites is suggested.
![Research paper thumbnail of Corrigendum to “Physical properties of phosponium ionic liquid and its mixtures with dodecane and water” [J. Chem. Thermodyn. 72 (2014) 54–64]](https://attachments.academia-assets.com/116496765/thumbnails/1.jpg)
](The Journal of Chemical Thermodynamics, 2016
The Journal of Chemical Thermodynamics, 2014
Addition of molecular solvents, dodecane and water, to the hydrophobic phosphonium ionic liquid (... more Addition of molecular solvents, dodecane and water, to the hydrophobic phosphonium ionic liquid (IL) tetradecyltrihexylphosphonium bis-(2,4,4-trimethylpentyl)phosphinate decreases its density and viscosity significantly. These changes have been studied in the temperature interval between 15 and 60°C and explained in terms of structural changes. Dependences of density and viscosity on the composition of binary and ternary systems are strongly nonlinear. Excess molar volumes and thermal expansion coefficients have been estimated for dry and water saturated solvents with IL. Strong H-bonding in water saturated solvents has been concluded from large negative excess molar volumes and strong temperature dependence of the density in water saturated solvents. VFT, Litovitz and Arrhenius models were tested for the correlation of temperature dependence of pure IL viscosity, showing that IL is a typical strong liquid. Deviations of the viscosity of the solvents to the ideal mixture viscosity based on the Eyring's theory of absolute rates were evaluated. In dynamic light scattering measurements, two different types of aggregates have been identified in the dry and water saturated solvents, with the mean size above 300 and 2 nm, respectively. High content of water of up to 8 molecules per ion pair of IL points to the existence of reverse micelles in the water containing solvents with hydrophobic IL.
Separation and Purification Technology, 2012
ABSTRACT A new promising process for the regeneration of solvents with ionic liquid (IL) by short... more ABSTRACT A new promising process for the regeneration of solvents with ionic liquid (IL) by short-path distillation (SPD) has been proposed and its application potential analyzed by simulation. Main advantage of this process compared to classical stripping with alkali solution is that the product is in form of free acid, not its salt and the consumption of chemicals is reduced. The model loaded solvent with phosphonium IL from membrane based solvent extraction (MBSE) of butyric acid (BA) was regenerated by two stage SPD at the temperature of 130 and 160 °C and pressure of 13 and 2 kPa, respectively. SPD was combined with extraction of BA from the dodecane phase of distillates by water. Yield of BA in distillates was 89%. The concentration factors of BA in both concentrates compared to BA concentration in the fermentation broth were of 25 and 43, respectively, for the dodecane content in the dry solvent containing 70 mass% of IL. Overall theoretical heat consumption in SPD was 3410 kJ per kg of recovered BA. The simulation has shown that both the yield of BA in MBSE and the mass flux of the solvent in MBSE are strongly influenced by the residual content of BA in recycled dodecane after the extraction of BA. Both parameters play a key role in the process performance. Additional experimental data on MBSE, SPD and dodecane extraction are needed for design and optimization of the hybrid process.
Separation and Purification Technology, 2013
ABSTRACT A new ammonium ionic liquid (IL), trialkylmethylammonium bis-(2,4,4-trimethylpentyl)phos... more ABSTRACT A new ammonium ionic liquid (IL), trialkylmethylammonium bis-(2,4,4-trimethylpentyl)phosphinate, has been synthesized from its precursors Aliquat 336 and Cyanex 272 by the metathesis reaction. Saturated water content in this hydrophobic IL and its 0.724 kmol m�3 solution in dodecane is as high as 22.4 and 13.9 mass%, respectively. This points to the presence of water-IL clusters and reverse micelles at lower IL concentrations identified by DLS measurements. Equilibrium data in the extraction of butyric acid (BA) into this IL and its 0.724 kmol m�3 solution in dodecane are presented. Experimental results have shown that the new ammonium IL is a good extractant of BA, with the distribution coefficient of over 80 at low BA concentrations in aqueous phase. The loading of the IL with extracted BA in experiments ranges up to 7, suggesting that IL forms complexes with multiple molecules of BA in chain. Water content in the organic phase initially sharply decreases with the increasing concentration of the extracted BA due to the water clusters and reverse micelles breakage. Dry IL is practically a non-flowing gel but when saturated with water or BA and/or mixed with dodecane, its viscosity decreases by more than two orders of magnitude. Thermogravimetric analysis has shown thermal stability of this IL at temperatures of up to 150 �C
Reactive and Functional Polymers, 2011
Equilibrium and kinetics of extraction of butyric acid (BA) into solvent impregnated resins (SIRs... more Equilibrium and kinetics of extraction of butyric acid (BA) into solvent impregnated resins (SIRs) have been studied. Microporous Amberlite XAD-1180N was impregnated with a new ammonium ionic liquid (IL) trialkylmethylammonium-bis(2,4,4-trimethylpentyl)phosphinate or with its solution in dodecane. No difference in BA extraction equilibrium between the free organic phases and the same phase impregnated in SIRs has been observed. This shows that
Desalination and Water Treatment, 2011
Desalination, 2009
Based on experimental data, a simulation and optimisation of the adsorption Ámicrofiltration (AMF... more Based on experimental data, a simulation and optimisation of the adsorption Ámicrofiltration (AMF) process for boron removal from reverse osmosis (RO) permeate was done. An impressively low flow rate of the dry boron adsorbent of about only 54.3 kg h (1 is needed in the adsorbent recirculation loop of a unit for treatment of 100 m 3 h (1 of RO permeate and boron concentration in the feed and raffinate 1.2 and 0.4 mg dm (3 , respectively. The optimum concentrations of dry adsorbent in the suspension leaving submerged microfiltration module (MF1) and cross-flow microfilters are 110 and 200 kg m (3 , respectively. A diafiltration of regenerated adsorbent suspension is an effective way of decreasing of adsorbent flow rate and consumption of chemicals in the desorption loop. Use of about 0.5% of the raffinate for diafiltration is optimal. Specific consumption of regeneration media per unit volume of raffinate at these conditions are 0.97 and 0.19 mol m (3 for acid and alkali, respectively. Segmentation of submerged MF1 module is a useful way of reducing membrane area needed, which is at an optimal conditions in case of ideal mixing in segmented and non-segmented MF1 modules 1315 and 1695 m 2 , respectively. The overall theoretical power input for MF pumps and air blower is of about 0.018 kWh m (3 .
Desalination, 2009
Suspensions of a microparticulate boron adsorbent can be effectively concentrated to relatively h... more Suspensions of a microparticulate boron adsorbent can be effectively concentrated to relatively high concentrations of about 11 mass% by microfiltration in aerated submerged modules using hydrophilic capillary and hydrophobic polypropylene hollow fibre membranes. With the increasing trans-membrane pressure difference, the permeate flux increases significantly at suspension concentrations below 7 and 4 mass% for hydrophilic and hydrophobic membrane, respectively. The permeate flux is higher for the hydrophilic membrane than for the hydrophobic one. Concentration dependence of flux for the hydrophilic membrane shows only a slight decrease of the flux with increasing concentration of the suspension, up to 7 mass%, while the flux through the hydrophobic membrane decreases much in this interval. The permeate flux at the trans-membrane pressure of 40 kPa for suspensions with 7 mass% of the adsorbent is about 72 and 14 dm 3 m (2 h (1 for the hydrophilic and the hydrophobic membrane, respectively. Backwashing of the membrane with a reversed flow of permeate was tested in a module with a hydrophilic membrane and was found successful in keeping the membrane performance stable for a shorter term of operation.
Chemical Papers, 2010
Simulation of a hybrid fermentation-separation process for the production of butyric acid (BA) ba... more Simulation of a hybrid fermentation-separation process for the production of butyric acid (BA) based on published data was done. A unit consisting of a bioreactor with immobilized cells in the fibrous bed and of separation by pertraction through supported liquid membranes (SLM) was considered. Productivities of the unit volume of a fixed bed bioreactor in continuous and fed-batch fermentation at pH 5.5 and 6.0 were used. Concentration of BA in the bioreactor outlet stream was assumed to be in the interval from 0.11 kmol m−3 to 0.45 kmol m−3. Data on the pertraction through SLM with phosphonium ionic liquid (IL) and bulk liquid membrane with trioctylamine (TOA) as carriers were used. A strong increase in the required membrane area was found for both carriers at the pH of pertraction above 4. pH values of fermentation and pertraction should be optimized independently. It is advantageous to have pH of the feed into the pertraction unit of about 4. Dependences of the membrane area on th...
Chemical Papers, 2011
A promising new process for the regeneration of solvents with ionic liquid by molecular distillat... more A promising new process for the regeneration of solvents with ionic liquid by molecular distillation has been proposed. The main advantage of this process compared with the classic stripping of acids with alkali solution is that the volatile organic acid is recovered with a yield of about 88 % in the form of free acid, not as its salt. Furthermore, improvement on the yield of the stripping can be assumed. The consumption of chemicals in stripping by molecular distillation is reduced.
Chemical Papers, 2011
Transport of butyric acid (BA) through a supported liquid membrane (SLM) containing phosphonium i... more Transport of butyric acid (BA) through a supported liquid membrane (SLM) containing phosphonium ionic liquid (IL) Cyphos IL-104 and dodecane occurs by two mechanisms. The first is related to the physical solubility of undissociated acid in dodecane in the form of a monomer or dimer and the second to the reactive extraction of acid by IL. Although the model of pertraction indicates that increasing the mean concentration of acid in the feed, c F,lmv, increases the participation of pertraction based on the physical solubility; in the tested range of c F,lmv from 0 kmol m−3 to 0.45 kmol m−3 it does not play an important role and at the highest c F,lmv value, less than 10 % of the overall BA transport were achieved. The presence of IL in SLM considerably increases the value of the overall mass transfer coefficient in pertraction at low BA concentrations. However, at c F,lmv > 0.4 kmol m−3 its values are similar for SLMs with and without IL. Compared to lactic acid, the pertraction of ...
Separation and Purification Technology, 2018
Separations account for approximately 50% of all manufacturing costs, making the selection of the... more Separations account for approximately 50% of all manufacturing costs, making the selection of the proper technology, and a potential affinity separation agent (ASA) of essential importance for process design. This selection is not straightforward. In this paper, aspects of fluid separation technologies, including shortcut calculations to estimate heat duties, are reviewed and applied to create insights in ab initio fluid separation process selection without extensive process simulations. It was found that composition and state of the feed can have major impacts on the minimal required heat duty, as well as the desired product purity. Distillation of dilute feeds is intrinsically hindered by a low internal efficiency and solvent based separations should be considered. Furthermore, the minimal heat duty for liquid-liquid extraction (LLX) with high boiling solvents is primarily feed composition dependent, while for low boiling solvents the solvent to feed ratio is important. This is also the case for the minimal duty for extractive distillation (ED) with light solvents, whereas the minimal duty of ED using high boiling solvents is independent of the composition, and generally higher than the minimal LLX duty. ED can be operated with only two columns, whereas LLX generally requires at least three, leading to higher capital costs. The feed composition dependence of the LLX minimal heat duty can result in a feed compositional break-even point when comparing LLX with ED. Using these theoretical insights in fluid separations, a series of industrial cases was reviewed and critical aspects in technology selection, and solvent selection and design such as selectivity and capacity are discussed. The results confirm the applicability of the minimal heat duty approach as a quick prediction tool for opportunities of solvent based technologies, as well as the need for including other considerations such as the number of required columns (capital costs) and the possibility to recover sensible heat.
International Journal of Environmental Research and Public Health, Nov 22, 2021
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Energy Efficiency, Jun 25, 2019
Intending to contribute to the discourse about industrial energy efficiency and barriers to its i... more Intending to contribute to the discourse about industrial energy efficiency and barriers to its improvement, deep insight into the scope and methodology and achievements of an energy audit on a Catalytic Naphtha Reforming Unit are provided. The audit of this particular unit was a part of the audit of the whole SLOVNAFT refinery in 2010-2012. The audit itself is the preparation of saving proposals' implementation and postimplementation monitoring and targeting that lasted until spring 2016 covered in retrospective as the auditors were involved in all post-auditing phases as well. Several saving ideas emerging from the performed audit were rejected or have still not been implemented due to either technical issues or non-technical factors. Implemented proposals included improvement in the condensates' management system, boiler feedwater preparation, and increased exploitation of the cogeneration potential. A cumulative 3-year benefit of over 600 k€ is reported which is close to the targeted value. The postaudit cooperation of auditors with the refinery's staff enabled to define the non-technical barriers to saving proposals' adoption that are of general nature. These included (1) short payback period requirement, (2) possibility of implementation of changes during the turnaround/general revisions, (3) conflicting relationships between local micro-economies of production units and the net-economy of the whole refinery, (4) internal processes and communication, and (5) personnel policy. Long-term cooperation, winning the trust and support of the staff and managers, and regular monitoring and targeting of implemented measures are seen as essential parts of sustainable industrial energy efficiency improvement in any industrial energy auditing.
The Journal of Chemical Thermodynamics, Feb 1, 2016
International Journal of Environmental Research and Public Health, 2021
Steam crackers (ethylene plants) belong to the most complex industrial plants and offer significa... more Steam crackers (ethylene plants) belong to the most complex industrial plants and offer significant potential for energy-saving translated into the reduction of greenhouse gas emissions. Steam export to or import from adjacent units or complexes can boost the associated financial benefit, but its energy and environmental impact are questionable. A study was carried out on a medium-capacity ethylene plant using field data to: 1. Estimate the energy savings potential achievable by optimizing internal steam management and optimizing steam export/import; 2. Quantify the associated change in air pollutant emissions; 3. Analyze the impact of the increasing carbon price on the measures adopted. Internal steam management optimization yielded steam let-down rate minimization and resulted in a 5% (87 TJ/year) reduction in steam cracker’s steam boiler fuel consumption and the associated cut of CO2 emissions by almost 4900 t/year and that of NOx emissions by more than 5 t/year. Steam import to ...
Large industrial production plants utilize steam as process and heating medium typically at least... more Large industrial production plants utilize steam as process and heating medium typically at least at two pressure levels. Such industrial facilities are also typically equipped with high pressure steam boilers and backpressure or/and condensing steam turbines, to cogenerate both process/heating steam and electricity for own consumption at the same time. Steam produced in steam turbines and exported from the cogeneration unit often undergoes pressure control step prior being consumed in the process or condensed in a heat exchanger. Contributing to production process stability on the one hand, such pressure reduction may result in decrease of cogenerated electric energy amount. In our study, we focused on paper machines as large steam consumers in papermaking process and the impact of low and medium pressure steam utilization in a thermocompressor installed in a particular paper machine on the RES-based cogeneration unit electric energy output. Thermocompressor is often applied in ind...
Energy Efficiency, 2019
Intending to contribute to the discourse about industrial energy efficiency and barriers to its i... more Intending to contribute to the discourse about industrial energy efficiency and barriers to its improvement, deep insight into the scope and methodology and achievements of an energy audit on a Catalytic Naphtha Reforming Unit are provided. The audit of this particular unit was a part of the audit of the whole SLOVNAFT refinery in 2010-2012. The audit itself is the preparation of saving proposals' implementation and postimplementation monitoring and targeting that lasted until spring 2016 covered in retrospective as the auditors were involved in all post-auditing phases as well. Several saving ideas emerging from the performed audit were rejected or have still not been implemented due to either technical issues or non-technical factors. Implemented proposals included improvement in the condensates' management system, boiler feedwater preparation, and increased exploitation of the cogeneration potential. A cumulative 3-year benefit of over 600 k€ is reported which is close to the targeted value. The postaudit cooperation of auditors with the refinery's staff enabled to define the non-technical barriers to saving proposals' adoption that are of general nature. These included (1) short payback period requirement, (2) possibility of implementation of changes during the turnaround/general revisions, (3) conflicting relationships between local micro-economies of production units and the net-economy of the whole refinery, (4) internal processes and communication, and (5) personnel policy. Long-term cooperation, winning the trust and support of the staff and managers, and regular monitoring and targeting of implemented measures are seen as essential parts of sustainable industrial energy efficiency improvement in any industrial energy auditing.
Energy Efficiency, 2019
BFWH Boiler feedwater heater BL Black liquor CCT Condensates collection tank CONC Concentrator CO... more BFWH Boiler feedwater heater BL Black liquor CCT Condensates collection tank CONC Concentrator COND Condenser DEA Deaerator ECO Economizer ESP Electrostatic precipitator FG Flue gas FGC Flue gas cooler HDS High dry solids HERB High energy regeneration boiler HPS High pressure steam (around 20 bar(g)) HW Hot water LPS Low pressure steam (around 5 bar (g)) MPS Middle pressure steam (around 11 bar (g)) OH Operating hours (per year) P&P Pulp & paper RS Reference state ST Steam turbine TIC Total investment cost VHPS Very high pressure steam (above 40 bar (g)) W Intercept of steam turbine working characteristics in Eqs.
Chemical Papers, 2017
An overview on specific phenomena in extraction of carboxylic acids with hydrophobic ionic liquid... more An overview on specific phenomena in extraction of carboxylic acids with hydrophobic ionic liquids (ILs) based on results of new measurements with selected phosphonium, ammonium and imidazolium ILs and published data is presented. Formation of IL-acid hydrated complexes with multiple molecules of organic acid per one IL ion pair was observed. The distribution coefficient of carboxylic acids and water content in ILs strongly decreases with the increasing acid concentration. Dependence of water content in the solvent passes through a minimum at loading of IL with butyric acid of about 3. Two extraction mechanisms are involved: competitive extraction of acid and water with the release of water from the solvent and co-extraction of water with acid depending on the IL concentration. A strong synergistic effect was observed between the cation and anion of ILs enhancing their extractive properties compared to IL precursors. A new extraction model suggests the formation of water bridges and polar nano-channels which is in agreement with the molecular modelling results. ILs are nano-segregated liquids with a structure sensitive to the content of molecular compounds. Water and carboxylic acids accumulate in polar domains and dodecane in non-polar domains modifying the IL structure and decreasing the solvent phase viscosity. The hypothesis of hopping mechanism in polar channels for acid molecules transport between acid chains at IL binding sites is suggested.
The Journal of Chemical Thermodynamics, 2016
The Journal of Chemical Thermodynamics, 2014
Addition of molecular solvents, dodecane and water, to the hydrophobic phosphonium ionic liquid (... more Addition of molecular solvents, dodecane and water, to the hydrophobic phosphonium ionic liquid (IL) tetradecyltrihexylphosphonium bis-(2,4,4-trimethylpentyl)phosphinate decreases its density and viscosity significantly. These changes have been studied in the temperature interval between 15 and 60°C and explained in terms of structural changes. Dependences of density and viscosity on the composition of binary and ternary systems are strongly nonlinear. Excess molar volumes and thermal expansion coefficients have been estimated for dry and water saturated solvents with IL. Strong H-bonding in water saturated solvents has been concluded from large negative excess molar volumes and strong temperature dependence of the density in water saturated solvents. VFT, Litovitz and Arrhenius models were tested for the correlation of temperature dependence of pure IL viscosity, showing that IL is a typical strong liquid. Deviations of the viscosity of the solvents to the ideal mixture viscosity based on the Eyring's theory of absolute rates were evaluated. In dynamic light scattering measurements, two different types of aggregates have been identified in the dry and water saturated solvents, with the mean size above 300 and 2 nm, respectively. High content of water of up to 8 molecules per ion pair of IL points to the existence of reverse micelles in the water containing solvents with hydrophobic IL.
Separation and Purification Technology, 2012
ABSTRACT A new promising process for the regeneration of solvents with ionic liquid (IL) by short... more ABSTRACT A new promising process for the regeneration of solvents with ionic liquid (IL) by short-path distillation (SPD) has been proposed and its application potential analyzed by simulation. Main advantage of this process compared to classical stripping with alkali solution is that the product is in form of free acid, not its salt and the consumption of chemicals is reduced. The model loaded solvent with phosphonium IL from membrane based solvent extraction (MBSE) of butyric acid (BA) was regenerated by two stage SPD at the temperature of 130 and 160 °C and pressure of 13 and 2 kPa, respectively. SPD was combined with extraction of BA from the dodecane phase of distillates by water. Yield of BA in distillates was 89%. The concentration factors of BA in both concentrates compared to BA concentration in the fermentation broth were of 25 and 43, respectively, for the dodecane content in the dry solvent containing 70 mass% of IL. Overall theoretical heat consumption in SPD was 3410 kJ per kg of recovered BA. The simulation has shown that both the yield of BA in MBSE and the mass flux of the solvent in MBSE are strongly influenced by the residual content of BA in recycled dodecane after the extraction of BA. Both parameters play a key role in the process performance. Additional experimental data on MBSE, SPD and dodecane extraction are needed for design and optimization of the hybrid process.
Separation and Purification Technology, 2013
ABSTRACT A new ammonium ionic liquid (IL), trialkylmethylammonium bis-(2,4,4-trimethylpentyl)phos... more ABSTRACT A new ammonium ionic liquid (IL), trialkylmethylammonium bis-(2,4,4-trimethylpentyl)phosphinate, has been synthesized from its precursors Aliquat 336 and Cyanex 272 by the metathesis reaction. Saturated water content in this hydrophobic IL and its 0.724 kmol m�3 solution in dodecane is as high as 22.4 and 13.9 mass%, respectively. This points to the presence of water-IL clusters and reverse micelles at lower IL concentrations identified by DLS measurements. Equilibrium data in the extraction of butyric acid (BA) into this IL and its 0.724 kmol m�3 solution in dodecane are presented. Experimental results have shown that the new ammonium IL is a good extractant of BA, with the distribution coefficient of over 80 at low BA concentrations in aqueous phase. The loading of the IL with extracted BA in experiments ranges up to 7, suggesting that IL forms complexes with multiple molecules of BA in chain. Water content in the organic phase initially sharply decreases with the increasing concentration of the extracted BA due to the water clusters and reverse micelles breakage. Dry IL is practically a non-flowing gel but when saturated with water or BA and/or mixed with dodecane, its viscosity decreases by more than two orders of magnitude. Thermogravimetric analysis has shown thermal stability of this IL at temperatures of up to 150 �C
Reactive and Functional Polymers, 2011
Equilibrium and kinetics of extraction of butyric acid (BA) into solvent impregnated resins (SIRs... more Equilibrium and kinetics of extraction of butyric acid (BA) into solvent impregnated resins (SIRs) have been studied. Microporous Amberlite XAD-1180N was impregnated with a new ammonium ionic liquid (IL) trialkylmethylammonium-bis(2,4,4-trimethylpentyl)phosphinate or with its solution in dodecane. No difference in BA extraction equilibrium between the free organic phases and the same phase impregnated in SIRs has been observed. This shows that
Desalination and Water Treatment, 2011
Desalination, 2009
Based on experimental data, a simulation and optimisation of the adsorption Ámicrofiltration (AMF... more Based on experimental data, a simulation and optimisation of the adsorption Ámicrofiltration (AMF) process for boron removal from reverse osmosis (RO) permeate was done. An impressively low flow rate of the dry boron adsorbent of about only 54.3 kg h (1 is needed in the adsorbent recirculation loop of a unit for treatment of 100 m 3 h (1 of RO permeate and boron concentration in the feed and raffinate 1.2 and 0.4 mg dm (3 , respectively. The optimum concentrations of dry adsorbent in the suspension leaving submerged microfiltration module (MF1) and cross-flow microfilters are 110 and 200 kg m (3 , respectively. A diafiltration of regenerated adsorbent suspension is an effective way of decreasing of adsorbent flow rate and consumption of chemicals in the desorption loop. Use of about 0.5% of the raffinate for diafiltration is optimal. Specific consumption of regeneration media per unit volume of raffinate at these conditions are 0.97 and 0.19 mol m (3 for acid and alkali, respectively. Segmentation of submerged MF1 module is a useful way of reducing membrane area needed, which is at an optimal conditions in case of ideal mixing in segmented and non-segmented MF1 modules 1315 and 1695 m 2 , respectively. The overall theoretical power input for MF pumps and air blower is of about 0.018 kWh m (3 .
Desalination, 2009
Suspensions of a microparticulate boron adsorbent can be effectively concentrated to relatively h... more Suspensions of a microparticulate boron adsorbent can be effectively concentrated to relatively high concentrations of about 11 mass% by microfiltration in aerated submerged modules using hydrophilic capillary and hydrophobic polypropylene hollow fibre membranes. With the increasing trans-membrane pressure difference, the permeate flux increases significantly at suspension concentrations below 7 and 4 mass% for hydrophilic and hydrophobic membrane, respectively. The permeate flux is higher for the hydrophilic membrane than for the hydrophobic one. Concentration dependence of flux for the hydrophilic membrane shows only a slight decrease of the flux with increasing concentration of the suspension, up to 7 mass%, while the flux through the hydrophobic membrane decreases much in this interval. The permeate flux at the trans-membrane pressure of 40 kPa for suspensions with 7 mass% of the adsorbent is about 72 and 14 dm 3 m (2 h (1 for the hydrophilic and the hydrophobic membrane, respectively. Backwashing of the membrane with a reversed flow of permeate was tested in a module with a hydrophilic membrane and was found successful in keeping the membrane performance stable for a shorter term of operation.
Chemical Papers, 2010
Simulation of a hybrid fermentation-separation process for the production of butyric acid (BA) ba... more Simulation of a hybrid fermentation-separation process for the production of butyric acid (BA) based on published data was done. A unit consisting of a bioreactor with immobilized cells in the fibrous bed and of separation by pertraction through supported liquid membranes (SLM) was considered. Productivities of the unit volume of a fixed bed bioreactor in continuous and fed-batch fermentation at pH 5.5 and 6.0 were used. Concentration of BA in the bioreactor outlet stream was assumed to be in the interval from 0.11 kmol m−3 to 0.45 kmol m−3. Data on the pertraction through SLM with phosphonium ionic liquid (IL) and bulk liquid membrane with trioctylamine (TOA) as carriers were used. A strong increase in the required membrane area was found for both carriers at the pH of pertraction above 4. pH values of fermentation and pertraction should be optimized independently. It is advantageous to have pH of the feed into the pertraction unit of about 4. Dependences of the membrane area on th...
Chemical Papers, 2011
A promising new process for the regeneration of solvents with ionic liquid by molecular distillat... more A promising new process for the regeneration of solvents with ionic liquid by molecular distillation has been proposed. The main advantage of this process compared with the classic stripping of acids with alkali solution is that the volatile organic acid is recovered with a yield of about 88 % in the form of free acid, not as its salt. Furthermore, improvement on the yield of the stripping can be assumed. The consumption of chemicals in stripping by molecular distillation is reduced.
Chemical Papers, 2011
Transport of butyric acid (BA) through a supported liquid membrane (SLM) containing phosphonium i... more Transport of butyric acid (BA) through a supported liquid membrane (SLM) containing phosphonium ionic liquid (IL) Cyphos IL-104 and dodecane occurs by two mechanisms. The first is related to the physical solubility of undissociated acid in dodecane in the form of a monomer or dimer and the second to the reactive extraction of acid by IL. Although the model of pertraction indicates that increasing the mean concentration of acid in the feed, c F,lmv, increases the participation of pertraction based on the physical solubility; in the tested range of c F,lmv from 0 kmol m−3 to 0.45 kmol m−3 it does not play an important role and at the highest c F,lmv value, less than 10 % of the overall BA transport were achieved. The presence of IL in SLM considerably increases the value of the overall mass transfer coefficient in pertraction at low BA concentrations. However, at c F,lmv > 0.4 kmol m−3 its values are similar for SLMs with and without IL. Compared to lactic acid, the pertraction of ...